Shaun Merrigan's Information Pages


Tag: Shaun Merrigan


Tektronix Scope-Mobile Cart Repair Part 1

Posted by Shaun Merrigan in Electronics, Oscilloscopes. Comments Off on Tektronix Scope-Mobile Cart Repair Part 1

6th January

Tektronix Scope-Mobile Cart Repair Part 1

I was lucky enough to obtain a Tektronix 202-2 Scope-Mobile Cart.

 

Upon examining it, I found that the scope tray was loose and the tilt mechanism did not function properly.  The cause for this was broken trunnion mounts on both sides of the cart as follows:

 

 

Three of the four bosses were fractured with the fracture surface indicating tensile overload.  I suspect that the bolts were overtightened and the bosses fractured. Overtightening loaded the bosses in tension by trying to compress the box frame member.  Unfortunately this type of polymer (some type of hard thermoplastic) is not good in tension.

Other mobile carts I have seen use cast aluminum for these trunnion mounts, which is a better choice for strength and durability.  The cart I have for my 556, a 205-2 (triple wide), uses cast aluminum trunnion mounts.

 

 

 

I … Read More »


New Vacuum Tube Box Scans

Posted by Shaun Merrigan in Electronics, Vacuum Tubes. Comments Off on New Vacuum Tube Box Scans

6th January

New Vacuum  Tube Box Scans

I have uploaded several new vacuum tube box scans including Philco, Canadian General Electric, Wards, and Hitachi (Hit-Ray):

 

 

Thanks,

 

Shaun M.


Tektronix 556 Dual Beam Oscilloscope Images

Posted by Shaun Merrigan in Electronics, Oscilloscopes, Tektronix 556, Vacuum Tubes. Comments Off on Tektronix 556 Dual Beam Oscilloscope Images

31st December

Tektronix 556 Dual Beam Oscilloscope Images

What follows is a series of images of my Tektronix 556 Dual Beam Oscilloscope displaying various waveforms.  I am learning about this scope and how to use it.

A brief description of the unit can be found here: Tektronix 556

 

Thanks for reading.

 

Shaun M.



Tektronix 556 Dual Beam Oscilloscope

Posted by Shaun Merrigan in Electronics, Oscilloscopes, Tektronix 556. Comments Off on Tektronix 556 Dual Beam Oscilloscope

5th December

Tektronix 556 Dual Beam Oscilloscope

I had recently the unique opportunity to acquire a complete Tektronix 556 Oscilloscope setup.  This comprised the oscilloscope itself, the matching scope cart, original manual, probes and 12 plug-in units.  This in itself is rare enough, but in addition, this particular scope has the optically desirable blue phosphor CRT and Tektronix C-27 Camera Bezel.   This 50 MHz bandwidth oscilloscope was the state of the art when it was introduced in the mid 1960’s: Tekwiki Tek 556

This will be the first of many posts and updates as I work my way through checking and restoring this beautiful scope.

And now some images:

Thanks!

 

Shaun Merrigan

 

 


Nest connectivity and charging problems solved

Posted by Shaun Merrigan in NEST Thermostat. Comments Off on Nest connectivity and charging problems solved

9th November

Nest connectivity and charging problems solved:

I have two NEST thermostats; one first generation and one second generation.  I experienced intermittent connectivity issues with my gen1 Nest soon after I installed it.  Initially I determined that it was not charging properly so I brought out the “C” (AC Common) wire from my furnace control board to the NEST and the charging problem was solved.  When I  installed the gen2 NEST, I made sure the “C” wire was available at installation.  I have no charging problems with either NEST now.

 

Connectivity problems would come and go, sometimes going many weeks or months between incidents.  I tried many solutions (port forwarding .lease times, static ip, etc) with varying degrees of success.  The connectivity problems were irritating rather than debilitating; most of the time the NEST worked fine.  The same pattern occurred after I installed … Read More »


Landscape Photo Diary Updated

Posted by Shaun Merrigan in News, Site Updates. Comments Off on Landscape Photo Diary Updated

30th June

Landscape Photo Diary Updated

I recently had the opportunity to photograph the area around Drumheller, Alberta.  This is a spectacular and beautiful area of Alberta. I took time to walk and drive parts of the now abandoned CN Drumheller Subdivision (CN Rail).  This particular subdivision winds its way through some wonderful areas of the Alberta Badlands.

I have put up a selection of my landscape and railway images on my photo website:  Drumheller Badlands, Spring 2014

 

Enjoy the wonderful Alberta Summer!

 

Shaun M


Nest thermostat: Should I assign an IP or Not?

Posted by Shaun Merrigan in NEST Thermostat, News, Tech. Comments Off on Nest thermostat: Should I assign an IP or Not?

25th June

Nest thermostat: Should I assign an IP or Not?

The question is: Does assigning the NEST thermostat a static IP using your router result in a more reliable wireless connection?  For my first generation NEST running v4.2.3 of the NEST software, the answer is a definite no.

Background:

I am using my home router as a DHCP  server in order to assign IP addresses to various devices behind it.  This is the typical default behavior of most home routers.  I like to tweak the setup, however and assign static IP addresses to various devices so that troubleshooting is simplified and  IP address conflicts are avoided.

My NEST thermostat connectivity had been generally very good, until a couple of weeks ago when I found that the NEST thermostat could not connect reliably to my router.  (I had updated my router firmware about that time as … Read More »


The Nike FuelBand: 5 Months On

Posted by Shaun Merrigan in News, Tech. Comments Off on The Nike FuelBand: 5 Months On

15th November

The Nike Fuel Band: 5 Months On

I purchased a Nike Fuel Band in late June 2013 with an idea that I could use it as a step counter over the summer and during the winter.  I did quite a bit of research, and examined competing products. While other products had more features, the Nike FuelBand was elegantly simple, easy to use, looked great and had the best software support (I do not use Android devices).  Since receiving it in June, I have used it continuously for over 5 months, and I am still using it.  How do I feel about it?  I love it.  It is easy to wear, rugged, and easy to use.   No gimmicks, no BS; it just works.

I love statistics, so the hourly, daily, weekly, monthly and yearly charts on the Nike website are great.  I can … Read More »


No Video Card Upgrade this round: No compelling reason

Posted by Shaun Merrigan in Gaming, News, Tech. Comments Off on No Video Card Upgrade this round: No compelling reason

15th November

No Video Card Upgrade this round: No compelling reason

AMD recently came out with their reference design for the R9 series of video cards (Hawaii Chipset): R9 Video Cards Overview .  I have read the reviews and the benchmarks, including comparisons to the 7990, GTX690 and Titan.  I see no compelling reason to “upgrade” my GTX690.  In fact, based on the benchmarks and reviews I have read GTX690 to R9 290X is more of a downgrade in power consumption, noise and mulit-monitor (2560 x 1600 X3) performance.  Crossfire is out of the question, since it does not support individual monitor color calibration, and I don’t even want to think about the TDP of such a setup.

I have looked through many benchmarks which have the GTX690 and HD7990 in the top spot for most games at the resolution I mentioned above.  The … Read More »


New Vacuum tube box scans

Posted by Shaun Merrigan in Site Updates, Tech, Vacuum Tubes. Comments Off on New Vacuum tube box scans

29th October

New Vacuum tube box scans

I have added several new images to my gallery of Vacuum Tube Box Artwork.

The new images include Westinghouse, Tung-Sol and Quality Brand tube boxes.

 

 

Shaun M